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<div class="titlepage"><div><div><h6 class="title">
<a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1"></a><a class="link" href="overload1.html" title="websocket::stream::async_accept (1 of 3 overloads)">websocket::stream::async_accept
          (1 of 3 overloads)</a>
</h6></div></div></div>
<p>
            Perform the WebSocket handshake asynchronously in the server role.
          </p>
<h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h0"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.synopsis"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.synopsis">Synopsis</a>
          </h7><pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">class</span> <span class="identifier">AcceptHandler</span> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special">&lt;</span><a class="link" href="../executor_type.html" title="websocket::stream::executor_type">executor_type</a><span class="special">&gt;&gt;</span>
<a href="../../../../../../../../doc/html/boost_asio/reference/asynchronous_operations.html#boost_asio.reference.asynchronous_operations.automatic_deduction_of_initiating_function_return_type" target="_top"><span class="emphasis"><em>DEDUCED</em></span></a>
<span class="identifier">async_accept</span><span class="special">(</span>
    <span class="identifier">AcceptHandler</span><span class="special">&amp;&amp;</span> <span class="identifier">handler</span> <span class="special">=</span> <span class="identifier">net</span><span class="special">::</span><span class="identifier">default_completion_token_t</span><span class="special">&lt;</span> <a class="link" href="../executor_type.html" title="websocket::stream::executor_type">executor_type</a> <span class="special">&gt;{});</span>
</pre>
<h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h1"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.description"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.description">Description</a>
          </h7><p>
            This initiating function is used to asynchronously begin performing the
            <a href="https://en.wikipedia.org/wiki/WebSocket#Protocol_handshake" target="_top">WebSocket
            handshake</a>, required before messages can be sent and received.
            During the handshake, the client sends the Websocket Upgrade HTTP request,
            and the server replies with an HTTP response indicating the result of
            the handshake. This call always returns immediately. The asynchronous
            operation will continue until one of the following conditions is true:
          </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem">
                The request is received and the response is sent.
              </li>
<li class="listitem">
                An error occurs.
              </li>
</ul></div>
<p>
            The algorithm, known as a <span class="emphasis"><em>composed asynchronous operation</em></span>,
            is implemented in terms of calls to the next layer's <code class="computeroutput"><span class="identifier">async_read_some</span></code>
            and <code class="computeroutput"><span class="identifier">async_write_some</span></code>
            functions. No other operation may be performed on the stream until this
            operation completes. If a valid upgrade request is received, an HTTP
            response with a <a href="https://tools.ietf.org/html/rfc7230#section-3.1.2" target="_top">status-code</a>
            of <a class="link" href="../../boost__beast__http__status.html" title="http::status"><code class="computeroutput"><span class="identifier">beast</span><span class="special">::</span><span class="identifier">http</span><span class="special">::</span><span class="identifier">status</span><span class="special">::</span><span class="identifier">switching_protocols</span></code></a> is sent
            to the peer, otherwise a non-successful error is associated with the
            operation. If the request size exceeds the capacity of the stream's internal
            buffer, the error <a class="link" href="../../boost__beast__websocket__error.html" title="websocket::error"><code class="computeroutput"><span class="identifier">error</span><span class="special">::</span><span class="identifier">buffer_overflow</span></code></a> will be indicated.
            To handle larger requests, an application should read the HTTP request
            directly using <a class="link" href="../../boost__beast__http__async_read.html" title="http::async_read"><code class="computeroutput">
            <span class="identifier">http</span><span class="special">::</span><span class="identifier">async_read</span> </code></a> and then pass the
            request to the appropriate overload of <a class="link" href="../accept.html" title="websocket::stream::accept"><code class="computeroutput"><span class="identifier">accept</span></code></a> or <a class="link" href="../async_accept.html" title="websocket::stream::async_accept"><code class="computeroutput"><span class="identifier">async_accept</span></code></a>
          </p>
<h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h2"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.parameters"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.parameters">Parameters</a>
          </h7><div class="informaltable"><table class="table">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                    <p>
                      Name
                    </p>
                  </th>
<th>
                    <p>
                      Description
                    </p>
                  </th>
</tr></thead>
<tbody><tr>
<td>
                    <p>
                      <code class="computeroutput"><span class="identifier">handler</span></code>
                    </p>
                  </td>
<td>
                    <p>
                      The completion handler to invoke when the operation completes.
                      The implementation takes ownership of the handler by performing
                      a decay-copy. The equivalent function signature of the handler
                      must be:
                    </p>
<pre xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" class="table-programlisting"><span class="keyword">void</span> <span class="identifier">handler</span><span class="special">(</span>
    <span class="identifier">error_code</span> <span class="keyword">const</span><span class="special">&amp;</span> <span class="identifier">ec</span>    <span class="comment">// Result of operation</span>
<span class="special">);</span>
</pre>
                    <p>
                      Regardless of whether the asynchronous operation completes
                      immediately or not, the handler will not be invoked from within
                      this function. Invocation of the handler will be performed
                      in a manner equivalent to using <code class="computeroutput"><span class="identifier">net</span><span class="special">::</span><span class="identifier">post</span></code>.
                    </p>
                  </td>
</tr></tbody>
</table></div>
<h7><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.h3"></a>
            <span class="phrase"><a name="beast.ref.boost__beast__websocket__stream.async_accept.overload1.see_also"></a></span><a class="link" href="overload1.html#beast.ref.boost__beast__websocket__stream.async_accept.overload1.see_also">See
            Also</a>
          </h7><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
                <a href="https://tools.ietf.org/html/rfc6455#section-4.2" target="_top">Websocket
                Opening Handshake Server Requirements (RFC6455)</a>
              </li></ul></div>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2016-2019 Vinnie
      Falco<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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